The present invention relates to an apparatus and method for performing anastomosis, more particularly, using a plurality of interlocking fasteners that compress the anastomosed tissues together.
After surgical resection of a diseased or cancerous portion of a tubular organ, e.g., partial bowel resection, the severed ends of the organ must be reconnected, or anastomosed. In this type of operation there are certain common objectives, viz., (i) to restore the integrity of the organ, i.e., so that no leakage through the repair occurs (ii) hemostasis of severed blood vessels while preserving blood flow to healthy tissue proximate the wound (iii) avoidance of further tissue damage by the anastomosis procedure (iv) preservation of organ function e.g., by avoiding the obstruction of the lumen of the organ or restraining peristalsis, if applicable. Present medical techniques for connecting two sections of a hollow tubular organ include suturing, stapling or clamping the severed ends together, each method having strengths and weaknesses relative to meeting the foregoing objectives.
For example, suturing is not preferred in certain circumstances due to the inaccessibility of one or both of the ends to be joined and/or the time and high degree of mechanical skill involved for performing the anastomosis. Staplers may be used to reconnect a severed tubular organ with a circular ring of staples distributed around a circumference to connect the severed ends. The resulting connection is radially compliant, allowing peristalsis in the region of the anastomosis, however, care must be taken to avoid over compression or incomplete apposition of the tissue. Since combined tissue thickness can vary by as much as 2 millimeters from patient to patient, the surgeon must adjust the stapler and resultant crimp length of the staples to accommodate the thicknesses that may be encountered. Further, the metallic staples are not absorbable.
The permanence of metallic anastomotic staples has been addressed by biodegradable anastomotic fastening systems which break down in the presence of bodily fluids at a predetermined rate. For example, U.S. Pat. No. 5,250,058 describes a biodegradable anastomotic fastener having a pair of plates, one of which has holes for receiving latching prongs protruding from the other plate. The plates are held in spaced relation on head and anvil sections, respectively, of an instrument that is inserted into the lumen of the organ to be repaired. The apposed ends of the organ are positioned between the fastener plates which are then drawn together by actuating the instrument. Fastening is accomplished through a singular linear motion in which the prongs of the first plate pierce the tissue then latch within the holes in the opposing plate. The excess tissue within the lumen is then cut by a cylindrical knife. The inner portion of each plate is also cut by the cylindrical knife to allow the instrument to be removed from the lumen of the organ. Known mechanized anastomosis fastening systems generally require tissue thickness to be measured to select an appropriate fastener and to avoid over compression or incomplete apposition. Accordingly, a variety of fastener sizes must be available to accommodate varying tissue thicknesses. In addition, known ring-type fastener systems provide a rigid anastomosis, limiting the radial expansion of the anastomosis and interrupting peristalsis.
The limitations of prior art surgical apparatus and methods for performing anastomosis are addressed by the present invention which includes a surgical fastener with a plurality of first portions having a first tissue constraining surface and a plurality of second portions having a second tissue constraining surface. The first portions are positionable proximate a first side of a bodily tissue, with the second portions positionable proximate a second side of the bodily tissue adjacent corresponding ones of the first portions. The first portions are extendable through the bodily tissue to contact the second portions and interlock therewith with the first tissue constraining surface positioned proximate the first side of the bodily tissue and resisting withdrawal of the first portions through the bodily tissue. The second tissue constraining surface is positioned proximate the second side of the bodily tissue resisting withdrawal of the second portion through the bodily tissue.
The fastener may be applied with a dispenser apparatus executing a method in accordance with the present invention, viz., the dispenser holds a plurality of individual fastener pairs, each having a first portion and a second portion, with the first portions on one side of the bodily tissue and the second portions on the other side. The dispenser ejects the first portions through the bodily tissue to contact the second portions and interlock therewith.